JG and FG are larger than what I was talking about, and so any number produced by them, while impressive, would not be the correct answer.
The information I have, as above, says that No 264 Squadron, flying Boulton Paul Defiants, shot down 28 Luftwaffe aircraft on the 20th of May, 1940 without loss to themselves.
The book that I am getting the information out of used German and British records for the Battle of Britain. For example, despite british claims of 184 enemy aircraft destroyed on September 15, 1940, the book gave the real total of 56 luftwaffe aircraft destroyed for 27 RAF fighters lost (The book had a photo of the front page of the September 16 London Times with the 184 claim splayed across to top). So I feel fairly confident that the authors did the research to back up 264 Squadron's claim.
Sisu
[This message has been edited by Karnak (edited 05-19-2000).]